1. Field of the Invention
In general, the present invention relates to containers that are designed to hold biologically active materials. More particularly, the present invention relates to the external structure of such containers and features of such containers that enable them to be supported within the confines of an autoclave for sterilization.
2. Description of the Prior Art
In the pharmaceutical industry, many biologically active compounds are routinely handled by scientists, lab technicians, quality control testers and the like. Some of these biologically active compounds are alive, in the form of bacteria, virus, molds and cell components. When these materials are tested, sampled or otherwise transported, the biologically active compounds are typically placed into stainless steel containers. The volume of the stainless steel containers can vary widely from a single ounce to many gallons.
The stainless steel containers used to transport biologically active compounds typically do not use threaded closures. Threaded closures provide confined areas between threads that may harbor contaminants. Due to the physical shape of the threads, it is very difficult to properly clean threads to the sanitary standards needed. It is for this reason that threaded closures are generally not used. Rather, what are used are flanged caps that are joined to the container with a clamp. The containers, the caps and the clamps are typically made from stainless steel so that all components can be sanitized in an autoclave prior to and after use. In this manner, the container, cap and clamp can be kept sterile so as not to introduce harmful contamination into the pharmaceutical product being transported or stored.
Containers that are designed to hold small volumes of material, i.e. less than one pint, often have weighted bottoms. This helps prevent the container from inadvertently tipping when resting on a surface. However, it also makes such small containers bottom heavy, and the entire container is very heavy for its size.
A problem therefore occurs when such small containers are to be cleaned in an autoclave. To clean a container in an autoclave, the container must be inverted so that contaminants do not get trapped within the container. However, since the containers have weighted bottoms, the containers are top heavy when inverted and tend to fall over easily. Furthermore, the containers often have plain external features that are designed to not harbor contamination. The lack of external features make it difficult to set the containers into conventional autoclave racks. The relatively large weight of the containers also prevents many containers from being placed on a single conventional rack. Additionally, the containers cannot be stacked atop one another within an autoclave, or else the areas of abutment between the heavy containers may harbor contamination.
A need therefore exists for a new container and rack assembly that can be used in an autoclave, wherein the container has a structure that does not harbor contamination yet enables the container to engage a rack. And, wherein the rack itself can hold many containers in a confined space without having the containers abut and harbor contamination. This need is met by the present invention as described and claimed below.